After the 21-year-old victim fell asleep aboard a northbound R train near the Whitehall Street subway station around 11:30 p.m. Sunday, an unidentified man stole her cell phone and woke her up, demanding a sex act in exchange for the return of the phone, police said.

Authorities said a struggle ensued between the man and woman after he attempted to steal additional property from her, according to WPIX.

When he was unsuccessful, he fled the train at Canal Street subway station with the victim's phone, police said.

EMS responded and transported the victim to an area hospital, according to police.

Authorities said the man wanted for questioning is described as in his mid 20s, standing about 5 feet, 10 inches tall, and weighing about 180 pounds. He was last seen wearing all dark clothing, and can be seen in the above surveillance footage released by police.